This invention relates to a computer aided design (CAD) system and, in particular, a computer aided design system (CAD) for use in manufacturing metal parts by processing a metal plate.
Conventionally, a wide variety of CAD systems have been proposed so as to design or draw various hardware products. Metal parts may be included in the products. At any rate, each of the conventional CAD systems is operated in accordance with a program which is prepared for each product and which may be called a CAD program.
On the other hand, disclosure is made by Ferriter et al in U.S. Pat. No. 4,875,162 as regards a method for automatic interfacing of a conceptual tool and a project management tool. Specifically, the method is carried out by using a system which implements a top-down functional approach to hardware product design and then automatically inputs the information gathered from the user to the project management tool by the use of the conceptual design tool. This system enables cost estimates at very early development phase of the product. As a result, such cost estimates serve to determine product feasibility. To this end, a relational database table is used to form a bill of material. The system might be suitable for manufacturing a lawnmower or the like, as exemplified in the referenced patent.
From this fact, it is readily understood that the method is effective to form a bill or list of materials, parts, and the like and serves as the automatic interfacing of the conceptual tool and the project management tool.
However, the method is not related to a CAD program. In addition, no consideration is directed to the CAD system which is for use in designing the metal parts which are manufactured through a processing step, a material selection step, a plating step, and a painting step.
Herein, it is to be noted that costs are varied at practically every step of manufacturing each of the metal parts because each of the metal parts is manufactured through the above-mentioned steps. In this connection, a cost of plating (plating cost) and a cost of painting (painting cost) should be successively summed up together with a processing cost and a material cost to calculate a total cost in metal plate processing.
Under the circumstances, cost estimates are practically made after a design of each of the metal parts is completed or finished by an engineer. Accordingly, when the cost estimates exceed an estimated cost, it is difficult to redesign each of the metal parts so as to reduce a cost.